Many computing and communications systems use an addressing system in which the most significant bit or bits of an address space are range bits identifying a range of addresses, and less significant bits are address bits identifying an address within the range. The address range may identify, for example, a type of device or resource, and the address bits may identify, for example, an address within the specified device or resource. Where several resources of the same type are present, the address bits may identify a specific resource, and an address within the specific resource.
Even quite similar computing systems may have address spaces of different sizes, and the size of address spaces is increasing over time as the real cost of hardware resources decreases.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.